UIPickerView 显示与隐藏

转载自  http://www.devdiv.com/home.php?mod=space&uid=45444&do=blog&id=6238

UIPickerView* pickerView = [[UIPickerView alloc] init];
[pickerView sizeToFit];
pickerView.autoresizingMask = (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight);
pickerView.delegate = self;
pickerView.dataSource = self;
pickerView.showsSelectionIndicator = YES;
self.yourPickerView = pickerView;  //UIPickerView

yourTextField.inputView = pickerView;

// create a done view + done button, attach to it a doneClicked action, and place it in a toolbar as an accessory input view...
// Prepare done button
UIToolbar* keyboardDoneButtonView = [[UIToolbar alloc] init];
keyboardDoneButtonView.barStyle = UIBarStyleBlack;
keyboardDoneButtonView.translucent = YES;
keyboardDoneButtonView.tintColor = nil;
[keyboardDoneButtonView sizeToFit];

UIBarButtonItem* doneButton = [[[UIBarButtonItem alloc] initWithTitle:@"Done"
    style:UIBarButtonItemStyleBordered target:self
    action:@selector(pickerDoneClicked:)] autorelease];

[keyboardDoneButtonView setItems:[NSArray arrayWithObjects:doneButton, nil]];

// Plug the keyboardDoneButtonView into the text field...
yourTextField.inputAccessoryView = keyboardDoneButtonView;  

[pickerView release];
[keyboardDoneButtonView release];